FERGUS FALLS, Minn. (AP) — Authorities say an Otter Tail County deputy was under the influence of the powerful painkiller fentanyl while involved in a high-speed chase that ended in a deadly crash.

Deputy Kelly Backman is charged with misconduct by a public officer and driving while intoxicated for the October incident that killed a couple in Fergus Falls.

Court documents show that Backman was in pursuit of a minivan driven by a man who was the subject of a drug investigation. The minivan allegedly ran a stop sign and caused a crash that killed 72-year-old Steve Christianson and his 71-year-old wife, Diane, both of Fergus Falls.

The complaint said that in addition to the fentanyl that was detected in his system, Backman tested positive for an anti-anxiety medication that had been prescribed.

Court documents do not show whether Backman has a lawyer. A phone number for Backman could not be obtained.

Court officials said Monday that a hearing date for Backman has not been scheduled.

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